Pfffff.. that's nothing.
Imagine a crowd of a few hundred people watching you start to fap.

Euhrm ... NSFW but rest assured, it's a projection on a big screen captured by a camera or a phone from the crowd. It's not a vid of a massive 'in your face cock'. (obviously, since it's on youtube).
Skip to 3:00 for the build up or 3:55 for the payoff.